There was a company called Sprowtt at 2009's TC 50 that wants to do this. They don't seem to be up and running though: http://www.techcrunch50.com/2009/sprowtt

There was a company called Sprowtt at 2009's TC 50 that wants to do this. They don't seem to be up and running though: http://www.techcrunch50.com/2009/sprowtt-marketplace/ http://www.techcrunch50.com/2009/sprowtt-marketplace/